const size_t
V3SvrBoolector::setTargetValue(const V3NetId& id, const V3BitVecX& value, const uint32_t& depth, const size_t& prev) {
// Construct formula y = b0 & b1' & b3 & ... & bn', and return expr y
if (prev) assert (!isNegFormula(prev)); // Constrain input prev expr should NOT be negative!
uint32_t size = value.size(); assert (size == _ntk->getNetWidth(id));
BtorExp* const aExp = getVerifyData(id, depth); assert (aExp);
BtorExp* pExp = (prev) ? boolector_copy(_Solver, getOriExp(prev)) : 0, *bExp, *cExp, *eExp;
char* bv_value = new char[size + 1];
uint32_t i = size, j = 0;
while (i--) {
if ('1' == value[i]) bv_value[j++] = '1';
else if ('0' == value[i]) bv_value[j++] = '0';
else if (j) {
bv_value[j] = '\0';
bExp = boolector_slice(_Solver, aExp, i + j, i + 1);
cExp = boolector_const(_Solver, bv_value);
eExp = boolector_eq(_Solver, bExp, cExp);
boolector_release(_Solver, bExp);
boolector_release(_Solver, cExp);
if (pExp) {
bExp = boolector_and(_Solver, pExp, eExp);
boolector_release(_Solver, pExp);
boolector_release(_Solver, eExp);
pExp = bExp;
}
else pExp = eExp;
j = 0;
}
}
if (j) {
bv_value[j] = '\0';
if (j == size) bExp = boolector_copy(_Solver, aExp);
else bExp = boolector_slice(_Solver, aExp, j - 1, 0);
cExp = boolector_const(_Solver, bv_value);
eExp = boolector_eq(_Solver, bExp, cExp);
boolector_release(_Solver, bExp);
boolector_release(_Solver, cExp);
if (pExp) {
bExp = boolector_and(_Solver, pExp, eExp);
boolector_release(_Solver, pExp);
boolector_release(_Solver, eExp);
pExp = bExp;
}
else pExp = eExp;
}
delete[] bv_value;
assert (!isNegFormula(getPosExp(pExp)));
return getPosExp(pExp);
}
int
main (void)
{
Btor *btor;
BtorNode *x, *y, *temp, *old_x, *old_y, *eq1, *eq2, *and, *formula;
int result;
btor = boolector_new ();
x = boolector_var (btor, BV1_EXAMPLE_NUM_BITS, NULL);
y = boolector_var (btor, BV1_EXAMPLE_NUM_BITS, NULL);
/* remember initial values of x and y */
old_x = boolector_copy (btor, x);
old_y = boolector_copy (btor, y);
/* x = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, x);
x = temp;
/* y = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, y);
y = temp;
/* x = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, x);
x = temp;
/* Now, we have to show that old_x = y and old_y = x */
eq1 = boolector_eq (btor, old_x, y);
eq2 = boolector_eq (btor, old_y, x);
and = boolector_and (btor, eq1, eq2);
/* In order to prove that this is a theorem, we negate the whole
* formula and show that the negation is unsatisfiable */
formula = boolector_not (btor, and);
/* We assert the formula and call Boolector */
boolector_assert (btor, formula);
result = boolector_sat (btor);
if (result == BOOLECTOR_UNSAT)
printf ("Formula is unsatisfiable\n");
else
abort ();
/* cleanup */
boolector_release (btor, x);
boolector_release (btor, old_x);
boolector_release (btor, y);
boolector_release (btor, old_y);
boolector_release (btor, eq1);
boolector_release (btor, eq2);
boolector_release (btor, and);
boolector_release (btor, formula);
assert (boolector_get_refs (btor) == 0);
boolector_delete (btor);
return 0;
}
literalt boolector_propt::land(const bvt &bv)
{
literalt l=new_variable();
u_int size=bv.size()+1;
BtorExp *args[size], *result;
for(unsigned int i=0; i<bv.size(); i++)
{
args[i] = boolector_literal(bv[i]);
if (i==1)
result = boolector_and(boolector_ctx, args[0], args[1]);
else if (i>1)
result = boolector_and(boolector_ctx, result, args[i]);
}
boolector_assert(boolector_ctx, boolector_iff(boolector_ctx, boolector_literal(l), result));
return l;
}
void
V3SvrBoolector::add_AND_Formula(const V3NetId& out, const uint32_t& depth) {
// Check Output Validation
assert (validNetId(out)); assert (!getVerifyData(out, depth));
assert ((AIG_NODE == _ntk->getGateType(out)) || (BV_AND == _ntk->getGateType(out)));
const uint32_t index = getV3NetIndex(out); assert (depth == _ntkData[index].size());
// Build AND I/O Relation
const V3NetId in1 = _ntk->getInputNetId(out, 0); assert (validNetId(in1));
const V3NetId in2 = _ntk->getInputNetId(out, 1); assert (validNetId(in2));
BtorExp* const exp1 = getVerifyData(in1, depth); assert (exp1);
BtorExp* const exp2 = getVerifyData(in2, depth); assert (exp2);
// Set BtorExp*
_ntkData[index].push_back(boolector_and(_Solver, exp1, exp2));
assert (getVerifyData(out, depth));
}
literalt boolector_propt::land(literalt a, literalt b)
{
if(a==const_literal(true)) return b;
if(b==const_literal(true)) return a;
if(a==const_literal(false)) return const_literal(false);
if(b==const_literal(false)) return const_literal(false);
if(a==b) return a;
literalt l=new_variable();
BtorExp *result;
result = boolector_and(boolector_ctx, boolector_literal(a), boolector_literal(b));
boolector_assert(boolector_ctx, boolector_iff(boolector_ctx, boolector_literal(l), result));
return l;
}
const size_t
V3SvrBoolector::setImplyIntersection(const V3SvrDataVec& Exps) {
if (Exps.size() == 0) return 0;
vector<size_t>::const_iterator it = Exps.begin(); assert (*it);
BtorExp *aExp = (isNegFormula(*it) ? boolector_not(_Solver, getOriExp(*it)) : boolector_copy(_Solver, getOriExp(*it)));
BtorExp *bExp, *oExp; ++it;
for (; it != Exps.end(); ++it) {
assert (*it); assert (aExp);
bExp = (isNegFormula(*it) ? boolector_not(_Solver, getOriExp(*it)) : boolector_copy(_Solver, getOriExp(*it)));
oExp = boolector_and(_Solver, aExp, bExp); assert (oExp);
boolector_release(_Solver, aExp);
boolector_release(_Solver, bExp);
aExp = oExp;
}
bExp = boolector_var(_Solver, 1, NULL);
oExp = boolector_implies(_Solver, bExp, aExp);
boolector_assert(_Solver, oExp);
boolector_release(_Solver, oExp);
boolector_release(_Solver, aExp);
assert (!isNegFormula(getPosExp(bExp)));
assert (bExp); return getPosExp(bExp);
}
int
main (void)
{
Btor *btor;
BtorNode *v1, *v2, *add, *zero, *vars_sgt_zero, *impl;
BtorNode *v1_sgt_zero, *v2_sgt_zero, *add_sgt_zero, *formula;
char *assignments[10];
int result, i;
btor = boolector_new ();
boolector_enable_model_gen (btor);
v1 = boolector_var (btor, BV2_EXAMPLE_NUM_BITS, NULL);
v2 = boolector_var (btor, BV2_EXAMPLE_NUM_BITS, NULL);
zero = boolector_zero (btor, BV2_EXAMPLE_NUM_BITS);
v1_sgt_zero = boolector_sgt (btor, v1, zero);
v2_sgt_zero = boolector_sgt (btor, v2, zero);
vars_sgt_zero = boolector_and (btor, v1_sgt_zero, v2_sgt_zero);
add = boolector_add (btor, v1, v2);
add_sgt_zero = boolector_sgt (btor, add, zero);
impl = boolector_implies (btor, vars_sgt_zero, add_sgt_zero);
/* We negate the formula and try to show that the negation is unsatisfiable */
formula = boolector_not (btor, impl);
/* We assert the formula and call Boolector */
boolector_assert (btor, formula);
result = boolector_sat (btor);
if (result == BOOLECTOR_SAT)
printf ("Instance is satisfiable");
else
abort ();
/* The formula is not valid, we have found a counter-example.
* Now, we are able to obtain assignments to arbitrary expressions */
i = 0;
assignments[i++] = boolector_bv_assignment (btor, zero);
assignments[i++] = boolector_bv_assignment (btor, v1);
assignments[i++] = boolector_bv_assignment (btor, v2);
assignments[i++] = boolector_bv_assignment (btor, add);
assignments[i++] = boolector_bv_assignment (btor, v1_sgt_zero);
assignments[i++] = boolector_bv_assignment (btor, v2_sgt_zero);
assignments[i++] = boolector_bv_assignment (btor, vars_sgt_zero);
assignments[i++] = boolector_bv_assignment (btor, add_sgt_zero);
assignments[i++] = boolector_bv_assignment (btor, impl);
assignments[i++] = boolector_bv_assignment (btor, formula);
i = 0;
printf ("Assignment to 0: %s\n", assignments[i++]);
printf ("Assignment to v1: %s\n", assignments[i++]);
printf ("Assignment to v2: %s\n", assignments[i++]);
printf ("Assignment to v1 + v2: %s\n", assignments[i++]);
printf ("Assignment to v1 > 0: %s\n", assignments[i++]);
printf ("Assignment to v2 > 0: %s\n", assignments[i++]);
printf ("Assignment to v1 > 0 & v2 > 0: %s\n", assignments[i++]);
printf ("Assignment to v1 + v2 > 0: %s\n", assignments[i++]);
printf ("Assignment to v1 > 0 & v2 > 0 => v1 + v2 > 0: %s\n",
assignments[i++]);
printf ("Assignment to !(v1 > 0 & v2 > 0 => v1 + v2 > 0): %s\n",
assignments[i++]);
for (i = 0; i < 10; i++)
boolector_free_bv_assignment (btor, assignments[i]);
/* cleanup */
boolector_release (btor, zero);
boolector_release (btor, v1);
boolector_release (btor, v2);
boolector_release (btor, add);
boolector_release (btor, impl);
boolector_release (btor, formula);
boolector_release (btor, v1_sgt_zero);
boolector_release (btor, v2_sgt_zero);
boolector_release (btor, vars_sgt_zero);
boolector_release (btor, add_sgt_zero);
assert (boolector_get_refs (btor) == 0);
boolector_delete (btor);
return 0;
}
